Mobile telephones are increasingly integrating applications such as multimedia players. It is thus possible to transfer data from a computer to a mobile telephone or to listen to music on a mobile telephone. These applications are managed and controlled by a central processing unit, such as a processor, which also controls the data transfers via a data transfer bus between a computer, for example, and a mobile telephone. Applications such as multimedia players require a large computing capacity percentage from the central processing unit. The remaining computing capacity percentage available for the central processing unit is then limited and it is not generally possible to make other applications operate at the same time, nor to carry out a data transfer on a serial transmission data transfer bus between a computer and the mobile telephone comprising the central processing unit.
As the power of a processor of a mobile telephone is limited, when a data transfer on a serial transmission data transfer bus is carried out between the mobile telephone and a computer, the processor limits the applications operating at the same time. Thus, in order to be able to benefit from other applications, such as a multimedia player, operating during a data transfer via a data transfer bus, it is generally necessary to have recourse to a more powerful processor or to an external coprocessor with an external random access memory.
However, in a mobile telephone, the space and the power of the processors are limited.